The invention relates to an arrangement for open-end friction spinning of the type with two adjacently arranged friction rollers driven in the same rotational direction and forming a wedge-shaped yarn forming gap which is at least partially accessable for purposes of maintenance, and with an inlet and opening device containing a fiber feed channel which opens in the area of the wedge-shaped gap.
With an arrangement for open-end friction spinning of the kind mentioned above such as described in European published unexamined application (EP-OS) No. 52 412, a fiber feed channel is arranged in a stationary housing. One of the two friction rollers which form the wedge-shaped gap is also stationarily arranged while the other roller is movably borne, whereby a swivel axis is provided at one end of the roller axle which swivel axis extends parallel to the plane defined by the two roller axles. The other end of this pivotable roller is guided in a slideway of a housing so that a precise return of the same is made possible while retaining the relative position. By outwardly pivoting the second roller, the wedge-shaped gap is made accessible in a limited manner for a maintenance process with this arrangement. With this complicated and expensive construction, however, the accessibility is only provided over and via the end faces of the rollers so that an eventually necessary cleaning process or the like becomes rather burdensome.
The invention is based upon the problem to construct an arrangement of the kind mentioned above in a simple manner so that the accessibility is improved for maintenance purposes, thereby increasing the servicing friendliness or servicability of the machine.
This problem is solved according to the invention by providing that the fiber feed channel includes at least two component parts divided by a partitioning line extending in the longitudinal direction to the channel, one of which component parts is movable away from the other component for exposing the wedge-shaped gap and at least the fiber feed opening area of the said channel.
With this construction according to the invention, the rollers which are arranged at close spacing and adjacently to each other need not be moved relative to one another during a maintenance process so that the tolerances necessary for dimensioning the wedge-shaped gap are more easily retained. In addition, however, the wedge-shaped gap, especially in the opening area of the fiber feed channel, is made accessible for a maintenance or servicing procedure so that this area can be very easily observed and eventually also cleaned. Furthermore, the fiber feed channel itself is exposed over at least a good portion of its entire length, making the servicing of the same possible. This is of special importance since greasy particles or even fibers may stick to the inner surfaces of the fiber feed channel during processing of natural fibers, whereby the spinning process may be greatly disturbed. The construction of the invention is altogether rather simple since only a relatively light component is being moved for the maintenance procedure.
According to a further feature of preferred embodiments of the invention it is provided that the movable component of the fiber feed channel is pivotably borne. It is thereby possible to readily remove this component out of the operational position, and return the same into its operational position without any additional adjustment. It is also suitable according to certain preferred embodiments to provide that the movable component of the fiber feed channel is retained in the operational position by means of a return spring. It is further advantageous to provide locking means for positioning and/or locking of parts into the operational position, which locking means are arranged at the movable component of the fiber feed channel and/or the other component. Higher tolerances are thereby permitted, especially for the bearing or guidance of the movable component, without unfavorably influencing the return of same to the exact operational position.
In order to avoid that fibers or the like are left behind in the area of the partitioning line between the fiber feed channel components, an advantageous feature of preferred embodiments of the invention is the provision of an atmospheric air gap remaining between the component parts of the fiber feed channel over a portion or the entire length of the partitioning line. Since the fiber feed channel is exposed to underpressure or subpressure, a small amount of air is then sucked in via the partitioning line gap, which air stream removes all fibers that would otherwise get caught therein.
In order to also expose other important parts of the fiber feed channel besides the wedge-shaped gap, a further feature of preferred embodiments of the invention is the provision that the movable component of the fiber feed channel forms at least one channel wall of the fiber feed channel having a rectangular cross section, which channel wall extends up to the opening or mouth of the fiber feed channel. By then removing this one part of the fiber feed channel, the feed channel is exposed in its entire cross section.
According to a further advantageous feature of certain preferred embodiments of the invention, the movable component of the fiber feed channel is provided with a projection means adjacent to the area of the fiber feed opening and covering the wedge shaped gap outside of the fiber feed opening area. This projection serves the purpose to prevent the infiltration of secondary or leaking air.
A further advantageous feature of preferred embodiments of the invention is the provision that the stationary component of the fiber feed channel is arranged at a housing surrounding an opening roller of the inlet and opening device. By attaching this stationary component of the fiber feed channel to the housing of the opening roller which is accomplished by, for example, a one part construction with the housing, a very precise positioning to the opening roller is necessarily achieved.
In certain preferred embodiments of the invention it is provided that the movable component of the fiber feed channel is retained at the lid covering the inlet and opening device as well as the friction rollers. Thereby, when the lid is opened the spinning unit is almost entirely exposed, together with the wedge-shaped gap, so that the areas of the inlet or supply roller, the opening roller, and the friction rollers forming the wedge-shaped gap can be observed, examined, and as necessary are accessible for a maintenance procedure.
According to certain other preferred embodiments of the invention it is provided that the movable component of the fiber feed channel is constructed as a lid covering the inlet and opening device and the rollers. The movable component part of the fiber feed channel is thereby assigned another function, namely the purpose of a cover. It can certainly also be provided according to embodiments contemplated by the invention that the cover is arranged as a closure for a housing surrounding the rollers.
Further objects, features, and advantages of the present invention will become more apparent from the following description when taken with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.